Notification of revised ISO Operating Procedure 4420 Draft Version Posted for Awareness

The California ISO has revised the operating procedure referenced below and posted for awareness.

4420 System Emergency, version 15.7, effective July 1, 2024.

Section 3.2.1: Moved Water agency contact up to four (4) to seven (7) days out and updated communications document from Summer Heat Event to Extreme Weather Event.

Sections 3.2.3.1 – 3.2.3.3: Updated language to clarify Exceptional Dispatch and market bidding steps.

Section 3.6.3: Added Metered Subsystem (MSS) resource step.

References: Updated status of the Strategic Reliability Reserve (SRR) resources and reformatting table sorting by BAA.

Removed history prior to five years.

The California ISO’s operating procedures are available on the Operating Procedures webpage.

Contact information

Please contact the CAISO/RC West Procedure Control Desk at ProcedureControl@caiso.com with any questions.